The scheme was constructed between 1983 and 1985, to provide drought relief water for Bayswater Power Station which was being constructed at the same time.
The scheme consists of:
a weir on the Barnard River, which transfers water into a small dam on Orham Creek via a gravity channel
a pair of pumping stations which pump the water through pipelines to Bralga Tops
another pipeline feeding downhill into Oaky Creek, which is a tributary of the Hunter River.
